Congressional Request
“Limiting the Magnitude
Of Future Climate Change”
Webinar for Chevron Corporation
By Professor Marilyn A. Brown
Georgia Institute of Technology
and Co-Chair of the “Limiting” Panel
June 28, 2010
The National Academies
 A private, non-profit organization charged to provide advice
to the Nation on science, engineering, and medicine.
 National Academy of Sciences (NAS) chartered in 1863;
National Academy of Engineering (NAE) and Institute of
Medicine (IOM) added later. The National Research
Council (NRC) is the operating arm of the NAS, NAE, and
IOM.
NAE
NAS
NRC
IOM
The National Academies
 Study committees produce consensus reports on a wide
range of topics.
 Committees are composed of experts who serve pro bono,
carefully chosen for expertise, balance, and objectivity
 All reports go through stringent peer-review and must be
approved by both the study committee and the institution.
Request from Congress
The Department of Commerce Appropriations Act of
2008 (Public Law 110-161) calls for the National Oceanic
and Atmospheric Administration (NOAA) to execute an
agreement with the National Academy of Sciences to:
“…investigate and study the serious and sweeping
issues relating to global climate change and make
recommendations regarding what steps must be taken
and what strategies must be adopted in response to
global climate change, including the science and
technology challenges thereof.”
Four Panel were established,
to address what can be done to:




limit the magnitude of climate change
adapt to the impacts of climate change
advance the science of climate change
inform effective decisions about climate change
A final report (of a committee composed of the panel
Chairs and vice-Chairs, plus others) will offer advice
on response strategies that look across these different
realms.
Charge to the ‘Limiting’ Panel
The Panel will describe, analyze, and assess strategies for
reducing the net future human influence on climate,
including both technology and policy options.
The Panel will focus on actions to reduce domestic
greenhouse gas emissions and other human drivers of
climate change (such as changes in land use), but will
also consider the international dimensions of climate
stabilization.
Panel Membership
Robert Fri (Chair), Resources for the Future
Marilyn Brown (Vice Chair), Georgia Institute of Technology
Doug Arent, National Renewable
Energy Laboratory
Ann Carlson, UCLA
Majora Carter, Majora Carter Group
Leon Clarke, Pacific Northwest
National Laboratory
Francisco de la Chesnaye, Electric
Power Research Institute
George Eads, Charles Rivers Assoc.
Genevieve Giuliano, University of
Southern California
Andrew Hoffman, University of Michigan
Robert Keohane, Princeton University
Loren Lutzenhiser, Portland State Univ.
Bruce McCarl, Texas A&M University
Mack McFarland, DuPont
Mary Nichols, CA Air Resource Board
Edward Rubin, Carnegie Mellon Univ.
Thomas Tietenberg, Colby College (Ret.)
James Trainham III, Sundrop Fuels, Inc.
Take home messages
A robust U.S. response to climate change requires:
 Prompt, sustained efforts to reduce GHG emissions
 An inclusive national framework for aligning the goals and
efforts of actors at all levels
 Adaptable management of policy responses
Setting Goals
Target: limiting
global mean
temperature increase
What is a ‘safe’ amount of climate change?
(e.g., 2 deg, 3 deg)
Target: limiting
global atmospheric
GHG concentrations
(e.g., 450ppm, 550 ppm)
Target: limiting
global GHG emissions
(e.g. global emission budget,
or percent reduction)
Target: limiting
U.S. GHG emissions
(e.g. national emission budget,
or percent reduction)
How does GHG concentration translate into
global temperature change and other key
impacts?
How does a given level of emissions translate
into atmospheric GHG concentrations?
What is a ‘reasonable’ share of U.S. emission
reductions relative to the global targets?
To suggest a reasonable emissions budget
range and test its feasibility, the panel drew
upon:
Energy Modeling Forum (EMF)
A recently-published effort of 10 of the world’s leading
Integrated Assessment Models that relates global GHG
concentration goals to U.S. emission budget goals
(emf.stanford.edu/research/emf22/)
America’s Energy Future (AEF)
An NRC series of studies that examined the technical potential
for expanding use of efficiency, renewable electricity and fuels,
CCS, and nuclear energy.
(www.nationalacademies.org/energy)
Emissions Budget
We suggest that the U.S. establish a ‘budget’ for
cumulative GHG emissions over a set period of time.
We do not recommend a
specific budget number,
but offer a ‘representative’
budget range of:
170 - 200 gigatons (Gt)
of CO2-eq for 2012 - 2050.
Business-as-usual emissions
would consume this budget
well before 2050.
Based on analyses by the Energy Modeling Forum (EMF)
and America’s Energy Future (AEF), we conclude that an
emissions budget in the 170–200 Gt CO2-eq range could
be technically possible, but very difficult.
Within the electric power and transportation sectors,
essentially all available options would need to be
deployed at levels close to what has been estimated as
technically possible. These estimates, however, are
based on some very optimistic assumptions
THUS, there is a need to aggressively pursue all major
near-term emission reduction opportunities AND support
R&D for creating new options.
Limiting the Magnitude
of Future Climate Change
Estimating economic impact (cost) of
emissions reductions through 2050 are
sensitive to:
 Timing of emissions reductions
 Availability of advanced technology
 Availability and price of international
offsets
Early start and strong R&D program could
mitigate economic impacts (i.e., reduce total
cost)
Economic Impact
400
REFERENCE: continue
historical rates of
technology improvement
ADVANCED: more rapid
technological change
Indicates that the availability
of advanced technologies can
greatly lower the costs of
emission reductions.
350
$/tCO2-e (2005 U.S.$)
Projected price of CO2
emissions under two
scenarios:
300
Reference
Advanced
250
200
150
100
50
0
2020
2035
2050
Options to reduce CO2 emissions
-Reduce demand for goods & services requiring energy
-Improve the efficiency with which energy is used
-Expand the use of low- and zero- carbon energy sources
-Capture and sequester CO2 directly from the atmosphere
Core Recommendations
1. Adopt a mechanism for setting an economy-wide
carbon pricing system.
2. Complement the carbon price with policies to:
 realize the practical potential for energy efficiency and
low-emission energy sources in the electric and
transportation sectors;
 establish the feasibility of carbon capture and storage
and new nuclear technologies;
 accelerate the retirement, retrofitting or replacement of
GHG emission-intensive infrastructure.
3. Create new technology choices by investing heavily
in research and crafting policies to stimulate
innovation.
Core Recommendations (cont…)
4. Consider potential equity implications when designing
and implementing climate change limiting policies, with
special attention to disadvantaged populations.
5. Establish the United States as a leader to stimulate other
countries to adopt GHG reduction targets.
6. Enable flexibility and experimentation with policies to
reduce GHG emissions at regional, state, and local levels.
7. Design policies that balance durability and consistency
with flexibility and capacity for modification as we learn
from experience.
1. Adopt an economy-wide carbon pricing system
-- A price on GHG emissions (through cap-and-trade, taxes,
or a hybrid of the two) creates incentives for emission
reductions and markets for low-emission technologies.
A cap-and-trade system would be particularly compatible
with the concept of an emissions budget, and perhaps more
durable over time.
-- Evidence suggests that economic efficiency is best served
by avoiding free emission allowances and having a system
that is economy-wide rather than limited to particular sectors.
-- Domestic and international offsets can serve useful
purposes, but only if adequate certification, monitoring, and
verification of emission reductions are possible.
2. Complement the carbon pricing system.
Even with a strong carbon pricing system, timely emission
reductions can be inhibited by many barriers. Complimentary
policies are needed to focus on:
(i) Assuring rapid progress with near-term, high-leverage
emission reduction opportunities for producing electricity
(i.e. - increase energy efficiency and use of low GHG
electricity generation options such as renewables; advance
full-scale demonstration for CCS and new nuclear power)
(ii) Advancing efficiency and low GHG-emitting technologies
in the transportation sector
(iii) Accelerating the retirement, retrofitting, or replacement of
emissions-intensive infrastructure.
3. Create new technology choices
Significantly increase both government and privatesector funding for energy R&D
Establish and expand markets for low-GHG technologies
and more rapidly bring new technologies to
commercial scale
Foster workforce development and training
Improve understanding of how social and behavioral
dynamics interact with technology.
Invention
R&D
Innovation
Adoption
Diffusion
(new or better
product)
(early users;
niche markets)
(improved
technology)
Learning
By Doing
Learning
By Using
4. Consider equity implications when designing
and implementing climate change limiting
policies.
Disadvantaged groups likely to suffer disproportionately from
adverse impacts of climate change may also be adversely
affected by policies to limit climate change.
Monitor and consider options for minimizing adverse impacts on
these groups (e.g., providing relief from higher energy prices;
actively engaging these communities in planning efforts).
Major changes to our nation’s energy system will inevitably lead
to job gains in some sectors and regions, and losses in
others. We can smooth this transition through targeted
support for educational, training, and retraining programs
5. Establish the U.S. as a leader to stimulate
other countries to adopt GHG emissions
reduction targets
U.S. emissions reductions alone are not sufficient for
limiting future climate change. But what the U.S. does
about its own GHG emissions will have a major impact
on how other countries act.
Is likely necessary for U.S. engagement to continue to
operate at multiple levels (UNFCCC, bi-lateral/multilateral agreements; sectoral-based agreements)
International engagement will require both competitive and
cooperative efforts. Of particular value are S&T initiatives
that help developing countries limit emissions while
advancing sustainable economic development.
6. Enable flexibility and experimentation with
emission reduction policies at regional, state,
and local levels
Considerable state and local-level action to reduce emissions is
already underway, and offers a valuable laboratory for policy
experimentation and learning.
In some instances, it may be appropriate for state/local efforts
to be preempted by new federal programs, but this must be
balanced against the need for flexibility and innovation.
Avoid punishing those that have taken early action to limit
emissions, and ensure that states and localities have sufficient
resources to implement mandated national programs.
7. Design policies that balance durability and
consistency with flexibility and capacity for
modification as we learn from experience
Policies must remain durable for decades and be resistant to
undercutting by special interest pressures. Durability comes
from creating a constituency that benefits from the policy and
has a vested interest in maintaining it.
At the same time, policies must be sufficiently flexible to allow
for adaptation as we gain experience and understanding.
There are inherent tensions between these goals of durability
and adaptability, and it will be an ongoing challenge to find a
balance between them.
For more information:
Project Website:
http://americasclimatechoices.org/
For questions, contact:
Me at marilyn.brown@pubpolicy.gatech.edu
or Laurie Geller, NRC, lgeller@nas.edu
Report available from
National Academy Press
http://www.nap.edu/catalog.php?record_id=12785